fs/ext4/ext4.h

   1 /*
   2  *  ext4.h
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/include/linux/minix_fs.h
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  */
  15
  16 #ifndef _EXT4_H
  17 #define _EXT4_H
  18
  19 #include <linux/types.h>
  20 #include <linux/blkdev.h>
  21 #include <linux/magic.h>
  22 #include <linux/jbd2.h>
  23 #include <linux/quota.h>
  24 #include <linux/rwsem.h>
  25 #include <linux/rbtree.h>
  26 #include <linux/seqlock.h>
  27 #include <linux/mutex.h>
  28 #include <linux/timer.h>
  29 #include <linux/wait.h>
  30 #include <linux/blockgroup_lock.h>
  31 #include <linux/percpu_counter.h>
  32 #ifdef __KERNEL__
  33 #include <linux/compat.h>
  34 #endif
  35
  36 /*
  37  * The fourth extended filesystem constants/structures
  38  */
  39
  40 /*
  41  * Define EXT4FS_DEBUG to produce debug messages
  42  */
  43 #undef EXT4FS_DEBUG
  44
  45 /*
  46  * Debug code
  47  */
  48 #ifdef EXT4FS_DEBUG
  49 #define ext4_debug(f, a...)                                             \
  50         do {                                                            \
  51                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  52                         __FILE__, __LINE__, __func__);                  \
  53                 printk(KERN_DEBUG f, ## a);                             \
  54         } while (0)
  55 #else
  56 #define ext4_debug(f, a...)     do {} while (0)
  57 #endif
  58
  59 #define EXT4_ERROR_INODE(inode, fmt, a...) \
  60         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  61
  62 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
  63         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  64
  65 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
  66         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  67
  68 /* data type for block offset of block group */
  69 typedef int ext4_grpblk_t;
  70
  71 /* data type for filesystem-wide blocks number */
  72 typedef unsigned long long ext4_fsblk_t;
  73
  74 /* data type for file logical block number */
  75 typedef __u32 ext4_lblk_t;
  76
  77 /* data type for block group number */
  78 typedef unsigned int ext4_group_t;
  79
  80 /*
  81  * Flags used in mballoc's allocation_context flags field.
  82  *
  83  * Also used to show what's going on for debugging purposes when the
  84  * flag field is exported via the traceport interface
  85  */
  86
  87 /* prefer goal again. length */
  88 #define EXT4_MB_HINT_MERGE              0x0001
  89 /* blocks already reserved */
  90 #define EXT4_MB_HINT_RESERVED           0x0002
  91 /* metadata is being allocated */
  92 #define EXT4_MB_HINT_METADATA           0x0004
  93 /* first blocks in the file */
  94 #define EXT4_MB_HINT_FIRST              0x0008
  95 /* search for the best chunk */
  96 #define EXT4_MB_HINT_BEST               0x0010
  97 /* data is being allocated */
  98 #define EXT4_MB_HINT_DATA               0x0020
  99 /* don't preallocate (for tails) */
 100 #define EXT4_MB_HINT_NOPREALLOC         0x0040
 101 /* allocate for locality group */
 102 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 103 /* allocate goal blocks or none */
 104 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
 105 /* goal is meaningful */
 106 #define EXT4_MB_HINT_TRY_GOAL           0x0200
 107 /* blocks already pre-reserved by delayed allocation */
 108 #define EXT4_MB_DELALLOC_RESERVED       0x0400
 109 /* We are doing stream allocation */
 110 #define EXT4_MB_STREAM_ALLOC            0x0800
 111 /* Use reserved root blocks if needed */
 112 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 113
 114 struct ext4_allocation_request {
 115         /* target inode for block we're allocating */
 116         struct inode *inode;
 117         /* how many blocks we want to allocate */
 118         unsigned int len;
 119         /* logical block in target inode */
 120         ext4_lblk_t logical;
 121         /* the closest logical allocated block to the left */
 122         ext4_lblk_t lleft;
 123         /* the closest logical allocated block to the right */
 124         ext4_lblk_t lright;
 125         /* phys. target (a hint) */
 126         ext4_fsblk_t goal;
 127         /* phys. block for the closest logical allocated block to the left */
 128         ext4_fsblk_t pleft;
 129         /* phys. block for the closest logical allocated block to the right */
 130         ext4_fsblk_t pright;
 131         /* flags. see above EXT4_MB_HINT_* */
 132         unsigned int flags;
 133 };
 134
 135 /*
 136  * Logical to physical block mapping, used by ext4_map_blocks()
 137  *
 138  * This structure is used to pass requests into ext4_map_blocks() as
 139  * well as to store the information returned by ext4_map_blocks().  It
 140  * takes less room on the stack than a struct buffer_head.
 141  */
 142 #define EXT4_MAP_NEW            (1 << BH_New)
 143 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
 144 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
 145 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
 146 #define EXT4_MAP_UNINIT         (1 << BH_Uninit)
 147 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 148                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 149                                  EXT4_MAP_UNINIT)
 150
 151 struct ext4_map_blocks {
 152         ext4_fsblk_t m_pblk;
 153         ext4_lblk_t m_lblk;
 154         unsigned int m_len;
 155         unsigned int m_flags;
 156 };
 157
 158 /*
 159  * For delayed allocation tracking
 160  */
 161 struct mpage_da_data {
 162         struct inode *inode;
 163         sector_t b_blocknr;             /* start block number of extent */
 164         size_t b_size;                  /* size of extent */
 165         unsigned long b_state;          /* state of the extent */
 166         unsigned long first_page, next_page;    /* extent of pages */
 167         struct writeback_control *wbc;
 168         int io_done;
 169         int pages_written;
 170         int retval;
 171 };
 172
 173 /*
 174  * Flags for ext4_io_end->flags
 175  */
 176 #define EXT4_IO_END_UNWRITTEN   0x0001
 177 #define EXT4_IO_END_ERROR       0x0002
 178
 179 struct ext4_io_page {
 180         struct page     *p_page;
 181         atomic_t        p_count;
 182 };
 183
 184 #define MAX_IO_PAGES 128
 185
 186 typedef struct ext4_io_end {
 187         struct list_head        list;           /* per-file finished IO list */
 188         struct inode            *inode;         /* file being written to */
 189         unsigned int            flag;           /* unwritten or not */
 190         struct page             *page;          /* page struct for buffer write */
 191         loff_t                  offset;         /* offset in the file */
 192         ssize_t                 size;           /* size of the extent */
 193         struct work_struct      work;           /* data work queue */
 194         struct kiocb            *iocb;          /* iocb struct for AIO */
 195         int                     result;         /* error value for AIO */
 196         int                     num_io_pages;
 197         struct ext4_io_page     *pages[MAX_IO_PAGES];
 198 } ext4_io_end_t;
 199
 200 struct ext4_io_submit {
 201         int                     io_op;
 202         struct bio              *io_bio;
 203         ext4_io_end_t           *io_end;
 204         struct ext4_io_page     *io_page;
 205         sector_t                io_next_block;
 206 };
 207
 208 /*
 209  * Special inodes numbers
 210  */
 211 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 212 #define EXT4_ROOT_INO            2      /* Root inode */
 213 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 214 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 215 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 216 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 217 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 218 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 219
 220 /* First non-reserved inode for old ext4 filesystems */
 221 #define EXT4_GOOD_OLD_FIRST_INO 11
 222
 223 /*
 224  * Maximal count of links to a file
 225  */
 226 #define EXT4_LINK_MAX           65000
 227
 228 /*
 229  * Macro-instructions used to manage several block sizes
 230  */
 231 #define EXT4_MIN_BLOCK_SIZE             1024
 232 #define EXT4_MAX_BLOCK_SIZE             65536
 233 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 234 #define EXT4_MAX_BLOCK_LOG_SIZE         16
 235 #ifdef __KERNEL__
 236 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 237 #else
 238 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 239 #endif
 240 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 241 #ifdef __KERNEL__
 242 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 243 #else
 244 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 245 #endif
 246 #ifdef __KERNEL__
 247 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 248 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 249 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 250 #else
 251 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 252                                  EXT4_GOOD_OLD_INODE_SIZE : \
 253                                  (s)->s_inode_size)
 254 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 255                                  EXT4_GOOD_OLD_FIRST_INO : \
 256                                  (s)->s_first_ino)
 257 #endif
 258 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 259
 260 /*
 261  * Structure of a blocks group descriptor
 262  */
 263 struct ext4_group_desc
 264 {
 265         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 266         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 267         __le32  bg_inode_table_lo;      /* Inodes table block */
 268         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 269         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 270         __le16  bg_used_dirs_count_lo;  /* Directories count */
 271         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 272         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
 273         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 274         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 275         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 276         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 277         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 278         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 279         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 280         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 281         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 282         __u32   bg_reserved2[3];
 283 };
 284
 285 /*
 286  * Structure of a flex block group info
 287  */
 288
 289 struct flex_groups {
 290         atomic_t free_inodes;
 291         atomic_t free_blocks;
 292         atomic_t used_dirs;
 293 };
 294
 295 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 296 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 297 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 298
 299 /*
 300  * Macro-instructions used to manage group descriptors
 301  */
 302 #define EXT4_MIN_DESC_SIZE              32
 303 #define EXT4_MIN_DESC_SIZE_64BIT        64
 304 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 305 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 306 #ifdef __KERNEL__
 307 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 308 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 309 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 310 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 311 #else
 312 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 313 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 314 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 315 #endif
 316
 317 /*
 318  * Constants relative to the data blocks
 319  */
 320 #define EXT4_NDIR_BLOCKS                12
 321 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 322 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 323 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 324 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 325
 326 /*
 327  * Inode flags
 328  */
 329 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 330 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 331 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 332 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 333 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 334 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 335 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 336 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 337 /* Reserved for compression usage... */
 338 #define EXT4_DIRTY_FL                   0x00000100
 339 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 340 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 341 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 342 /* End compression flags --- maybe not all used */
 343 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 344 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 345 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 346 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 347 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 348 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 349 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 350 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 351 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 352 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
 353 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 354
 355 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
 356 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
 357
 358 /* Flags that should be inherited by new inodes from their parent. */
 359 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 360                            EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
 361                            EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 362                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 363                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 364
 365 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 366 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 367
 368 /* Flags that are appropriate for non-directories/regular files. */
 369 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 370
 371 /* Mask out flags that are inappropriate for the given type of inode. */
 372 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 373 {
 374         if (S_ISDIR(mode))
 375                 return flags;
 376         else if (S_ISREG(mode))
 377                 return flags & EXT4_REG_FLMASK;
 378         else
 379                 return flags & EXT4_OTHER_FLMASK;
 380 }
 381
 382 /*
 383  * Inode flags used for atomic set/get
 384  */
 385 enum {
 386         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 387         EXT4_INODE_UNRM         = 1,    /* Undelete */
 388         EXT4_INODE_COMPR        = 2,    /* Compress file */
 389         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 390         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 391         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 392         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 393         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 394 /* Reserved for compression usage... */
 395         EXT4_INODE_DIRTY        = 8,
 396         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 397         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 398         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
 399 /* End compression flags --- maybe not all used */
 400         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 401         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 402         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 403         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 404         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 405         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 406         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 407         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 408         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 409         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
 410         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 411 };
 412
 413 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 414 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
 415         printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
 416                 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
 417
 418 /*
 419  * Since it's pretty easy to mix up bit numbers and hex values, and we
 420  * can't do a compile-time test for ENUM values, we use a run-time
 421  * test to make sure that EXT4_XXX_FL is consistent with respect to
 422  * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
 423  * out so it won't cost any extra space in the compiled kernel image.
 424  * But it's important that these values are the same, since we are
 425  * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
 426  * must be consistent with the values of FS_XXX_FL defined in
 427  * include/linux/fs.h and the on-disk values found in ext2, ext3, and
 428  * ext4 filesystems, and of course the values defined in e2fsprogs.
 429  *
 430  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 431  */
 432 static inline void ext4_check_flag_values(void)
 433 {
 434         CHECK_FLAG_VALUE(SECRM);
 435         CHECK_FLAG_VALUE(UNRM);
 436         CHECK_FLAG_VALUE(COMPR);
 437         CHECK_FLAG_VALUE(SYNC);
 438         CHECK_FLAG_VALUE(IMMUTABLE);
 439         CHECK_FLAG_VALUE(APPEND);
 440         CHECK_FLAG_VALUE(NODUMP);
 441         CHECK_FLAG_VALUE(NOATIME);
 442         CHECK_FLAG_VALUE(DIRTY);
 443         CHECK_FLAG_VALUE(COMPRBLK);
 444         CHECK_FLAG_VALUE(NOCOMPR);
 445         CHECK_FLAG_VALUE(ECOMPR);
 446         CHECK_FLAG_VALUE(INDEX);
 447         CHECK_FLAG_VALUE(IMAGIC);
 448         CHECK_FLAG_VALUE(JOURNAL_DATA);
 449         CHECK_FLAG_VALUE(NOTAIL);
 450         CHECK_FLAG_VALUE(DIRSYNC);
 451         CHECK_FLAG_VALUE(TOPDIR);
 452         CHECK_FLAG_VALUE(HUGE_FILE);
 453         CHECK_FLAG_VALUE(EXTENTS);
 454         CHECK_FLAG_VALUE(EA_INODE);
 455         CHECK_FLAG_VALUE(EOFBLOCKS);
 456         CHECK_FLAG_VALUE(RESERVED);
 457 }
 458
 459 /* Used to pass group descriptor data when online resize is done */
 460 struct ext4_new_group_input {
 461         __u32 group;            /* Group number for this data */
 462         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 463         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 464         __u64 inode_table;      /* Absolute block number of inode table start */
 465         __u32 blocks_count;     /* Total number of blocks in this group */
 466         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 467         __u16 unused;
 468 };
 469
 470 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 471 struct compat_ext4_new_group_input {
 472         u32 group;
 473         compat_u64 block_bitmap;
 474         compat_u64 inode_bitmap;
 475         compat_u64 inode_table;
 476         u32 blocks_count;
 477         u16 reserved_blocks;
 478         u16 unused;
 479 };
 480 #endif
 481
 482 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 483 struct ext4_new_group_data {
 484         __u32 group;
 485         __u64 block_bitmap;
 486         __u64 inode_bitmap;
 487         __u64 inode_table;
 488         __u32 blocks_count;
 489         __u16 reserved_blocks;
 490         __u16 unused;
 491         __u32 free_blocks_count;
 492 };
 493
 494 /*
 495  * Flags used by ext4_map_blocks()
 496  */
 497         /* Allocate any needed blocks and/or convert an unitialized
 498            extent to be an initialized ext4 */
 499 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 500         /* Request the creation of an unitialized extent */
 501 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
 502 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
 503                                                  EXT4_GET_BLOCKS_CREATE)
 504         /* Caller is from the delayed allocation writeout path,
 505            so set the magic i_delalloc_reserve_flag after taking the
 506            inode allocation semaphore for */
 507 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 508         /* caller is from the direct IO path, request to creation of an
 509         unitialized extents if not allocated, split the uninitialized
 510         extent if blocks has been preallocated already*/
 511 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 512 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 513 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 514                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 515         /* Convert extent to initialized after IO complete */
 516 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 517                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 518         /* Punch out blocks of an extent */
 519 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
 520         /* Don't normalize allocation size (used for fallocate) */
 521 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 522
 523 /*
 524  * Flags used by ext4_free_blocks
 525  */
 526 #define EXT4_FREE_BLOCKS_METADATA       0x0001
 527 #define EXT4_FREE_BLOCKS_FORGET         0x0002
 528 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 529 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
 530
 531 /*
 532  * ioctl commands
 533  */
 534 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 535 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 536 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 537 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 538 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 539 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 540 #ifdef CONFIG_JBD2_DEBUG
 541 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
 542 #endif
 543 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 544 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 545 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 546 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 547 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 548  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 549  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 550 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 551 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 552
 553 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 554 /*
 555  * ioctl commands in 32 bit emulation
 556  */
 557 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 558 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 559 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 560 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 561 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 562 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 563 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 564 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 565 #ifdef CONFIG_JBD2_DEBUG
 566 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
 567 #endif
 568 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 569 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 570 #endif
 571
 572 /* Max physical block we can address w/o extents */
 573 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 574
 575 /*
 576  * Structure of an inode on the disk
 577  */
 578 struct ext4_inode {
 579         __le16  i_mode;         /* File mode */
 580         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 581         __le32  i_size_lo;      /* Size in bytes */
 582         __le32  i_atime;        /* Access time */
 583         __le32  i_ctime;        /* Inode Change time */
 584         __le32  i_mtime;        /* Modification time */
 585         __le32  i_dtime;        /* Deletion Time */
 586         __le16  i_gid;          /* Low 16 bits of Group Id */
 587         __le16  i_links_count;  /* Links count */
 588         __le32  i_blocks_lo;    /* Blocks count */
 589         __le32  i_flags;        /* File flags */
 590         union {
 591                 struct {
 592                         __le32  l_i_version;
 593                 } linux1;
 594                 struct {
 595                         __u32  h_i_translator;
 596                 } hurd1;
 597                 struct {
 598                         __u32  m_i_reserved1;
 599                 } masix1;
 600         } osd1;                         /* OS dependent 1 */
 601         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 602         __le32  i_generation;   /* File version (for NFS) */
 603         __le32  i_file_acl_lo;  /* File ACL */
 604         __le32  i_size_high;
 605         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 606         union {
 607                 struct {
 608                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 609                         __le16  l_i_file_acl_high;
 610                         __le16  l_i_uid_high;   /* these 2 fields */
 611                         __le16  l_i_gid_high;   /* were reserved2[0] */
 612                         __u32   l_i_reserved2;
 613                 } linux2;
 614                 struct {
 615                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 616                         __u16   h_i_mode_high;
 617                         __u16   h_i_uid_high;
 618                         __u16   h_i_gid_high;
 619                         __u32   h_i_author;
 620                 } hurd2;
 621                 struct {
 622                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 623                         __le16  m_i_file_acl_high;
 624                         __u32   m_i_reserved2[2];
 625                 } masix2;
 626         } osd2;                         /* OS dependent 2 */
 627         __le16  i_extra_isize;
 628         __le16  i_pad1;
 629         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 630         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 631         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 632         __le32  i_crtime;       /* File Creation time */
 633         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 634         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 635 };
 636
 637 struct move_extent {
 638         __u32 reserved;         /* should be zero */
 639         __u32 donor_fd;         /* donor file descriptor */
 640         __u64 orig_start;       /* logical start offset in block for orig */
 641         __u64 donor_start;      /* logical start offset in block for donor */
 642         __u64 len;              /* block length to be moved */
 643         __u64 moved_len;        /* moved block length */
 644 };
 645
 646 #define EXT4_EPOCH_BITS 2
 647 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 648 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 649
 650 /*
 651  * Extended fields will fit into an inode if the filesystem was formatted
 652  * with large inodes (-I 256 or larger) and there are not currently any EAs
 653  * consuming all of the available space. For new inodes we always reserve
 654  * enough space for the kernel's known extended fields, but for inodes
 655  * created with an old kernel this might not have been the case. None of
 656  * the extended inode fields is critical for correct filesystem operation.
 657  * This macro checks if a certain field fits in the inode. Note that
 658  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 659  */
 660 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 661         ((offsetof(typeof(*ext4_inode), field) +        \
 662           sizeof((ext4_inode)->field))                  \
 663         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 664             (einode)->i_extra_isize))                   \
 665
 666 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 667 {
 668        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 669                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 670                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 671 }
 672
 673 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 674 {
 675        if (sizeof(time->tv_sec) > 4)
 676                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 677                                << 32;
 678        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 679 }
 680
 681 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 682 do {                                                                           \
 683         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 684         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 685                 (raw_inode)->xtime ## _extra =                                 \
 686                                 ext4_encode_extra_time(&(inode)->xtime);       \
 687 } while (0)
 688
 689 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 690 do {                                                                           \
 691         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 692                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 693         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 694                 (raw_inode)->xtime ## _extra =                                 \
 695                                 ext4_encode_extra_time(&(einode)->xtime);      \
 696 } while (0)
 697
 698 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 699 do {                                                                           \
 700         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 701         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 702                 ext4_decode_extra_time(&(inode)->xtime,                        \
 703                                        raw_inode->xtime ## _extra);            \
 704         else                                                                   \
 705                 (inode)->xtime.tv_nsec = 0;                                    \
 706 } while (0)
 707
 708 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 709 do {                                                                           \
 710         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 711                 (einode)->xtime.tv_sec =                                       \
 712                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 713         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 714                 ext4_decode_extra_time(&(einode)->xtime,                       \
 715                                        raw_inode->xtime ## _extra);            \
 716         else                                                                   \
 717                 (einode)->xtime.tv_nsec = 0;                                   \
 718 } while (0)
 719
 720 #define i_disk_version osd1.linux1.l_i_version
 721
 722 #if defined(__KERNEL__) || defined(__linux__)
 723 #define i_reserved1     osd1.linux1.l_i_reserved1
 724 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 725 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 726 #define i_uid_low       i_uid
 727 #define i_gid_low       i_gid
 728 #define i_uid_high      osd2.linux2.l_i_uid_high
 729 #define i_gid_high      osd2.linux2.l_i_gid_high
 730 #define i_reserved2     osd2.linux2.l_i_reserved2
 731
 732 #elif defined(__GNU__)
 733
 734 #define i_translator    osd1.hurd1.h_i_translator
 735 #define i_uid_high      osd2.hurd2.h_i_uid_high
 736 #define i_gid_high      osd2.hurd2.h_i_gid_high
 737 #define i_author        osd2.hurd2.h_i_author
 738
 739 #elif defined(__masix__)
 740
 741 #define i_reserved1     osd1.masix1.m_i_reserved1
 742 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 743 #define i_reserved2     osd2.masix2.m_i_reserved2
 744
 745 #endif /* defined(__KERNEL__) || defined(__linux__) */
 746
 747 /*
 748  * storage for cached extent
 749  * If ec_len == 0, then the cache is invalid.
 750  * If ec_start == 0, then the cache represents a gap (null mapping)
 751  */
 752 struct ext4_ext_cache {
 753         ext4_fsblk_t    ec_start;
 754         ext4_lblk_t     ec_block;
 755         __u32           ec_len; /* must be 32bit to return holes */
 756 };
 757
 758 /*
 759  * fourth extended file system inode data in memory
 760  */
 761 struct ext4_inode_info {
 762         __le32  i_data[15];     /* unconverted */
 763         __u32   i_dtime;
 764         ext4_fsblk_t    i_file_acl;
 765
 766         /*
 767          * i_block_group is the number of the block group which contains
 768          * this file's inode.  Constant across the lifetime of the inode,
 769          * it is ued for making block allocation decisions - we try to
 770          * place a file's data blocks near its inode block, and new inodes
 771          * near to their parent directory's inode.
 772          */
 773         ext4_group_t    i_block_group;
 774         ext4_lblk_t     i_dir_start_lookup;
 775 #if (BITS_PER_LONG < 64)
 776         unsigned long   i_state_flags;          /* Dynamic state flags */
 777 #endif
 778         unsigned long   i_flags;
 779
 780 #ifdef CONFIG_EXT4_FS_XATTR
 781         /*
 782          * Extended attributes can be read independently of the main file
 783          * data. Taking i_mutex even when reading would cause contention
 784          * between readers of EAs and writers of regular file data, so
 785          * instead we synchronize on xattr_sem when reading or changing
 786          * EAs.
 787          */
 788         struct rw_semaphore xattr_sem;
 789 #endif
 790
 791         struct list_head i_orphan;      /* unlinked but open inodes */
 792
 793         /*
 794          * i_disksize keeps track of what the inode size is ON DISK, not
 795          * in memory.  During truncate, i_size is set to the new size by
 796          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 797          * set i_disksize to 0 until the truncate is actually under way.
 798          *
 799          * The intent is that i_disksize always represents the blocks which
 800          * are used by this file.  This allows recovery to restart truncate
 801          * on orphans if we crash during truncate.  We actually write i_disksize
 802          * into the on-disk inode when writing inodes out, instead of i_size.
 803          *
 804          * The only time when i_disksize and i_size may be different is when
 805          * a truncate is in progress.  The only things which change i_disksize
 806          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 807          */
 808         loff_t  i_disksize;
 809
 810         /*
 811          * i_data_sem is for serialising ext4_truncate() against
 812          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 813          * data tree are chopped off during truncate. We can't do that in
 814          * ext4 because whenever we perform intermediate commits during
 815          * truncate, the inode and all the metadata blocks *must* be in a
 816          * consistent state which allows truncation of the orphans to restart
 817          * during recovery.  Hence we must fix the get_block-vs-truncate race
 818          * by other means, so we have i_data_sem.
 819          */
 820         struct rw_semaphore i_data_sem;
 821         struct inode vfs_inode;
 822         struct jbd2_inode *jinode;
 823
 824         struct ext4_ext_cache i_cached_extent;
 825         /*
 826          * File creation time. Its function is same as that of
 827          * struct timespec i_{a,c,m}time in the generic inode.
 828          */
 829         struct timespec i_crtime;
 830
 831         /* mballoc */
 832         struct list_head i_prealloc_list;
 833         spinlock_t i_prealloc_lock;
 834
 835         /* ialloc */
 836         ext4_group_t    i_last_alloc_group;
 837
 838         /* allocation reservation info for delalloc */
 839         unsigned int i_reserved_data_blocks;
 840         unsigned int i_reserved_meta_blocks;
 841         unsigned int i_allocated_meta_blocks;
 842         ext4_lblk_t i_da_metadata_calc_last_lblock;
 843         int i_da_metadata_calc_len;
 844
 845         /* on-disk additional length */
 846         __u16 i_extra_isize;
 847
 848 #ifdef CONFIG_QUOTA
 849         /* quota space reservation, managed internally by quota code */
 850         qsize_t i_reserved_quota;
 851 #endif
 852
 853         /* completed IOs that might need unwritten extents handling */
 854         struct list_head i_completed_io_list;
 855         spinlock_t i_completed_io_lock;
 856         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
 857         /* current io_end structure for async DIO write*/
 858         ext4_io_end_t *cur_aio_dio;
 859         atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
 860
 861         spinlock_t i_block_reservation_lock;
 862
 863         /*
 864          * Transactions that contain inode's metadata needed to complete
 865          * fsync and fdatasync, respectively.
 866          */
 867         tid_t i_sync_tid;
 868         tid_t i_datasync_tid;
 869 };
 870
 871 /*
 872  * File system states
 873  */
 874 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 875 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 876 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 877
 878 /*
 879  * Misc. filesystem flags
 880  */
 881 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 882 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 883 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 884
 885 /*
 886  * Mount flags
 887  */
 888 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
 889 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 890 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 891 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 892 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 893 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 894 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 895 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 896 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 897 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 898 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 899 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 900 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 901 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 902 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 903 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 904 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 905 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 906 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 907 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 908 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 909 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
 910 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 911 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 912 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
 913 #define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
 914 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 915 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 916 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 917 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 918 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
 919
 920 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
 921                                                 ~EXT4_MOUNT_##opt
 922 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
 923                                                 EXT4_MOUNT_##opt
 924 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 925                                          EXT4_MOUNT_##opt)
 926
 927 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
 928                                                 ~EXT4_MOUNT2_##opt
 929 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
 930                                                 EXT4_MOUNT2_##opt
 931 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
 932                                          EXT4_MOUNT2_##opt)
 933
 934 #define ext4_set_bit                    __test_and_set_bit_le
 935 #define ext4_set_bit_atomic             ext2_set_bit_atomic
 936 #define ext4_clear_bit                  __test_and_clear_bit_le
 937 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
 938 #define ext4_test_bit                   test_bit_le
 939 #define ext4_find_first_zero_bit        find_first_zero_bit_le
 940 #define ext4_find_next_zero_bit         find_next_zero_bit_le
 941 #define ext4_find_next_bit              find_next_bit_le
 942
 943 /*
 944  * Maximal mount counts between two filesystem checks
 945  */
 946 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 947 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 948
 949 /*
 950  * Behaviour when detecting errors
 951  */
 952 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
 953 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
 954 #define EXT4_ERRORS_PANIC               3       /* Panic */
 955 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
 956
 957 /*
 958  * Structure of the super block
 959  */
 960 struct ext4_super_block {
 961 /*00*/  __le32  s_inodes_count;         /* Inodes count */
 962         __le32  s_blocks_count_lo;      /* Blocks count */
 963         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
 964         __le32  s_free_blocks_count_lo; /* Free blocks count */
 965 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
 966         __le32  s_first_data_block;     /* First Data Block */
 967         __le32  s_log_block_size;       /* Block size */
 968         __le32  s_obso_log_frag_size;   /* Obsoleted fragment size */
 969 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
 970         __le32  s_obso_frags_per_group; /* Obsoleted fragments per group */
 971         __le32  s_inodes_per_group;     /* # Inodes per group */
 972         __le32  s_mtime;                /* Mount time */
 973 /*30*/  __le32  s_wtime;                /* Write time */
 974         __le16  s_mnt_count;            /* Mount count */
 975         __le16  s_max_mnt_count;        /* Maximal mount count */
 976         __le16  s_magic;                /* Magic signature */
 977         __le16  s_state;                /* File system state */
 978         __le16  s_errors;               /* Behaviour when detecting errors */
 979         __le16  s_minor_rev_level;      /* minor revision level */
 980 /*40*/  __le32  s_lastcheck;            /* time of last check */
 981         __le32  s_checkinterval;        /* max. time between checks */
 982         __le32  s_creator_os;           /* OS */
 983         __le32  s_rev_level;            /* Revision level */
 984 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
 985         __le16  s_def_resgid;           /* Default gid for reserved blocks */
 986         /*
 987          * These fields are for EXT4_DYNAMIC_REV superblocks only.
 988          *
 989          * Note: the difference between the compatible feature set and
 990          * the incompatible feature set is that if there is a bit set
 991          * in the incompatible feature set that the kernel doesn't
 992          * know about, it should refuse to mount the filesystem.
 993          *
 994          * e2fsck's requirements are more strict; if it doesn't know
 995          * about a feature in either the compatible or incompatible
 996          * feature set, it must abort and not try to meddle with
 997          * things it doesn't understand...
 998          */
 999         __le32  s_first_ino;            /* First non-reserved inode */
1000         __le16  s_inode_size;           /* size of inode structure */
1001         __le16  s_block_group_nr;       /* block group # of this superblock */
1002         __le32  s_feature_compat;       /* compatible feature set */
1003 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1004         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1005 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1006 /*78*/  char    s_volume_name[16];      /* volume name */
1007 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1008 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1009         /*
1010          * Performance hints.  Directory preallocation should only
1011          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1012          */
1013         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1014         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1015         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1016         /*
1017          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1018          */
1019 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1020 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1021         __le32  s_journal_dev;          /* device number of journal file */
1022         __le32  s_last_orphan;          /* start of list of inodes to delete */
1023         __le32  s_hash_seed[4];         /* HTREE hash seed */
1024         __u8    s_def_hash_version;     /* Default hash version to use */
1025         __u8    s_jnl_backup_type;
1026         __le16  s_desc_size;            /* size of group descriptor */
1027 /*100*/ __le32  s_default_mount_opts;
1028         __le32  s_first_meta_bg;        /* First metablock block group */
1029         __le32  s_mkfs_time;            /* When the filesystem was created */
1030         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1031         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1032 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1033         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1034         __le32  s_free_blocks_count_hi; /* Free blocks count */
1035         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1036         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1037         __le32  s_flags;                /* Miscellaneous flags */
1038         __le16  s_raid_stride;          /* RAID stride */
1039         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1040         __le64  s_mmp_block;            /* Block for multi-mount protection */
1041         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1042         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1043         __u8    s_reserved_char_pad;
1044         __le16  s_reserved_pad;
1045         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1046         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1047         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1048         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1049                                               snapshot's future use */
1050         __le32  s_snapshot_list;        /* inode number of the head of the
1051                                            on-disk snapshot list */
1052 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1053         __le32  s_error_count;          /* number of fs errors */
1054         __le32  s_first_error_time;     /* first time an error happened */
1055         __le32  s_first_error_ino;      /* inode involved in first error */
1056         __le64  s_first_error_block;    /* block involved of first error */
1057         __u8    s_first_error_func[32]; /* function where the error happened */
1058         __le32  s_first_error_line;     /* line number where error happened */
1059         __le32  s_last_error_time;      /* most recent time of an error */
1060         __le32  s_last_error_ino;       /* inode involved in last error */
1061         __le32  s_last_error_line;      /* line number where error happened */
1062         __le64  s_last_error_block;     /* block involved of last error */
1063         __u8    s_last_error_func[32];  /* function where the error happened */
1064 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1065         __u8    s_mount_opts[64];
1066         __le32  s_reserved[112];        /* Padding to the end of the block */
1067 };
1068
1069 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1070
1071 #ifdef __KERNEL__
1072
1073 /*
1074  * run-time mount flags
1075  */
1076 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1077 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1078
1079 /*
1080  * fourth extended-fs super-block data in memory
1081  */
1082 struct ext4_sb_info {
1083         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1084         unsigned long s_inodes_per_block;/* Number of inodes per block */
1085         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1086         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1087         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1088         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1089         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1090         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1091         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1092         unsigned long s_overhead_last;  /* Last calculated overhead */
1093         unsigned long s_blocks_last;    /* Last seen block count */
1094         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1095         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1096         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1097         struct buffer_head **s_group_desc;
1098         unsigned int s_mount_opt;
1099         unsigned int s_mount_opt2;
1100         unsigned int s_mount_flags;
1101         ext4_fsblk_t s_sb_block;
1102         uid_t s_resuid;
1103         gid_t s_resgid;
1104         unsigned short s_mount_state;
1105         unsigned short s_pad;
1106         int s_addr_per_block_bits;
1107         int s_desc_per_block_bits;
1108         int s_inode_size;
1109         int s_first_ino;
1110         unsigned int s_inode_readahead_blks;
1111         unsigned int s_inode_goal;
1112         spinlock_t s_next_gen_lock;
1113         u32 s_next_generation;
1114         u32 s_hash_seed[4];
1115         int s_def_hash_version;
1116         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1117         struct percpu_counter s_freeblocks_counter;
1118         struct percpu_counter s_freeinodes_counter;
1119         struct percpu_counter s_dirs_counter;
1120         struct percpu_counter s_dirtyblocks_counter;
1121         struct blockgroup_lock *s_blockgroup_lock;
1122         struct proc_dir_entry *s_proc;
1123         struct kobject s_kobj;
1124         struct completion s_kobj_unregister;
1125
1126         /* Journaling */
1127         struct journal_s *s_journal;
1128         struct list_head s_orphan;
1129         struct mutex s_orphan_lock;
1130         struct mutex s_resize_lock;
1131         unsigned long s_commit_interval;
1132         u32 s_max_batch_time;
1133         u32 s_min_batch_time;
1134         struct block_device *journal_bdev;
1135 #ifdef CONFIG_JBD2_DEBUG
1136         struct timer_list turn_ro_timer;        /* For turning read-only (crash simulation) */
1137         wait_queue_head_t ro_wait_queue;        /* For people waiting for the fs to go read-only */
1138 #endif
1139 #ifdef CONFIG_QUOTA
1140         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1141         int s_jquota_fmt;                       /* Format of quota to use */
1142 #endif
1143         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1144         struct rb_root system_blks;
1145
1146 #ifdef EXTENTS_STATS
1147         /* ext4 extents stats */
1148         unsigned long s_ext_min;
1149         unsigned long s_ext_max;
1150         unsigned long s_depth_max;
1151         spinlock_t s_ext_stats_lock;
1152         unsigned long s_ext_blocks;
1153         unsigned long s_ext_extents;
1154 #endif
1155         /* ext4 extent cache stats */
1156         unsigned long extent_cache_hits;
1157         unsigned long extent_cache_misses;
1158
1159         /* for buddy allocator */
1160         struct ext4_group_info ***s_group_info;
1161         struct inode *s_buddy_cache;
1162         spinlock_t s_md_lock;
1163         unsigned short *s_mb_offsets;
1164         unsigned int *s_mb_maxs;
1165
1166         /* tunables */
1167         unsigned long s_stripe;
1168         unsigned int s_mb_stream_request;
1169         unsigned int s_mb_max_to_scan;
1170         unsigned int s_mb_min_to_scan;
1171         unsigned int s_mb_stats;
1172         unsigned int s_mb_order2_reqs;
1173         unsigned int s_mb_group_prealloc;
1174         unsigned int s_max_writeback_mb_bump;
1175         /* where last allocation was done - for stream allocation */
1176         unsigned long s_mb_last_group;
1177         unsigned long s_mb_last_start;
1178
1179         /* stats for buddy allocator */
1180         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1181         atomic_t s_bal_success; /* we found long enough chunks */
1182         atomic_t s_bal_allocated;       /* in blocks */
1183         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1184         atomic_t s_bal_goals;   /* goal hits */
1185         atomic_t s_bal_breaks;  /* too long searches */
1186         atomic_t s_bal_2orders; /* 2^order hits */
1187         spinlock_t s_bal_lock;
1188         unsigned long s_mb_buddies_generated;
1189         unsigned long long s_mb_generation_time;
1190         atomic_t s_mb_lost_chunks;
1191         atomic_t s_mb_preallocated;
1192         atomic_t s_mb_discarded;
1193         atomic_t s_lock_busy;
1194
1195         /* locality groups */
1196         struct ext4_locality_group __percpu *s_locality_groups;
1197
1198         /* for write statistics */
1199         unsigned long s_sectors_written_start;
1200         u64 s_kbytes_written;
1201
1202         unsigned int s_log_groups_per_flex;
1203         struct flex_groups *s_flex_groups;
1204
1205         /* workqueue for dio unwritten */
1206         struct workqueue_struct *dio_unwritten_wq;
1207
1208         /* timer for periodic error stats printing */
1209         struct timer_list s_err_report;
1210
1211         /* Lazy inode table initialization info */
1212         struct ext4_li_request *s_li_request;
1213         /* Wait multiplier for lazy initialization thread */
1214         unsigned int s_li_wait_mult;
1215
1216         /* Kernel thread for multiple mount protection */
1217         struct task_struct *s_mmp_tsk;
1218 };
1219
1220 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1221 {
1222         return sb->s_fs_info;
1223 }
1224 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1225 {
1226         return container_of(inode, struct ext4_inode_info, vfs_inode);
1227 }
1228
1229 static inline struct timespec ext4_current_time(struct inode *inode)
1230 {
1231         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1232                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1233 }
1234
1235 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1236 {
1237         return ino == EXT4_ROOT_INO ||
1238                 ino == EXT4_JOURNAL_INO ||
1239                 ino == EXT4_RESIZE_INO ||
1240                 (ino >= EXT4_FIRST_INO(sb) &&
1241                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1242 }
1243
1244 /*
1245  * Inode dynamic state flags
1246  */
1247 enum {
1248         EXT4_STATE_JDATA,               /* journaled data exists */
1249         EXT4_STATE_NEW,                 /* inode is newly created */
1250         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1251         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1252         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1253         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1254         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1255         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1256         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1257 };
1258
1259 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1260 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1261 {                                                                       \
1262         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1263 }                                                                       \
1264 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1265 {                                                                       \
1266         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1267 }                                                                       \
1268 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1269 {                                                                       \
1270         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1271 }
1272
1273 EXT4_INODE_BIT_FNS(flag, flags, 0)
1274 #if (BITS_PER_LONG < 64)
1275 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1276
1277 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1278 {
1279         (ei)->i_state_flags = 0;
1280 }
1281 #else
1282 EXT4_INODE_BIT_FNS(state, flags, 32)
1283
1284 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1285 {
1286         /* We depend on the fact that callers will set i_flags */
1287 }
1288 #endif
1289 #else
1290 /* Assume that user mode programs are passing in an ext4fs superblock, not
1291  * a kernel struct super_block.  This will allow us to call the feature-test
1292  * macros from user land. */
1293 #define EXT4_SB(sb)     (sb)
1294 #endif
1295
1296 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1297
1298 /*
1299  * Codes for operating systems
1300  */
1301 #define EXT4_OS_LINUX           0
1302 #define EXT4_OS_HURD            1
1303 #define EXT4_OS_MASIX           2
1304 #define EXT4_OS_FREEBSD         3
1305 #define EXT4_OS_LITES           4
1306
1307 /*
1308  * Revision levels
1309  */
1310 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1311 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1312
1313 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1314 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1315
1316 #define EXT4_GOOD_OLD_INODE_SIZE 128
1317
1318 /*
1319  * Feature set definitions
1320  */
1321
1322 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1323         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1324 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1325         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1326 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1327         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1328 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1329         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1330 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1331         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1332 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1333         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1334 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1335         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1336 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1337         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1338 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1339         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1340
1341 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1342 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1343 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1344 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1345 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1346 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1347
1348 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1349 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1350 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1351 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1352 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1353 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1354 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1355 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1356
1357 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1358 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1359 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1360 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1361 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1362 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1363 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1364 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1365 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1366 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1367 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1368
1369 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1370 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1371                                          EXT4_FEATURE_INCOMPAT_META_BG)
1372 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1373                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1374                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1375
1376 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1377 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1378                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1379                                          EXT4_FEATURE_INCOMPAT_META_BG)
1380 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1381                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1382                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1383
1384 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1385 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1386                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1387                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1388                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1389                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1390                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1391                                          EXT4_FEATURE_INCOMPAT_MMP)
1392 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1393                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1394                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1395                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1396                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1397                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1398                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
1399
1400 /*
1401  * Default values for user and/or group using reserved blocks
1402  */
1403 #define EXT4_DEF_RESUID         0
1404 #define EXT4_DEF_RESGID         0
1405
1406 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1407
1408 /*
1409  * Default mount options
1410  */
1411 #define EXT4_DEFM_DEBUG         0x0001
1412 #define EXT4_DEFM_BSDGROUPS     0x0002
1413 #define EXT4_DEFM_XATTR_USER    0x0004
1414 #define EXT4_DEFM_ACL           0x0008
1415 #define EXT4_DEFM_UID16         0x0010
1416 #define EXT4_DEFM_JMODE         0x0060
1417 #define EXT4_DEFM_JMODE_DATA    0x0020
1418 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1419 #define EXT4_DEFM_JMODE_WBACK   0x0060
1420 #define EXT4_DEFM_NOBARRIER     0x0100
1421 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1422 #define EXT4_DEFM_DISCARD       0x0400
1423 #define EXT4_DEFM_NODELALLOC    0x0800
1424
1425 /*
1426  * Default journal batch times
1427  */
1428 #define EXT4_DEF_MIN_BATCH_TIME 0
1429 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1430
1431 /*
1432  * Minimum number of groups in a flexgroup before we separate out
1433  * directories into the first block group of a flexgroup
1434  */
1435 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1436
1437 /*
1438  * Structure of a directory entry
1439  */
1440 #define EXT4_NAME_LEN 255
1441
1442 struct ext4_dir_entry {
1443         __le32  inode;                  /* Inode number */
1444         __le16  rec_len;                /* Directory entry length */
1445         __le16  name_len;               /* Name length */
1446         char    name[EXT4_NAME_LEN];    /* File name */
1447 };
1448
1449 /*
1450  * The new version of the directory entry.  Since EXT4 structures are
1451  * stored in intel byte order, and the name_len field could never be
1452  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1453  * file_type field.
1454  */
1455 struct ext4_dir_entry_2 {
1456         __le32  inode;                  /* Inode number */
1457         __le16  rec_len;                /* Directory entry length */
1458         __u8    name_len;               /* Name length */
1459         __u8    file_type;
1460         char    name[EXT4_NAME_LEN];    /* File name */
1461 };
1462
1463 /*
1464  * Ext4 directory file types.  Only the low 3 bits are used.  The
1465  * other bits are reserved for now.
1466  */
1467 #define EXT4_FT_UNKNOWN         0
1468 #define EXT4_FT_REG_FILE        1
1469 #define EXT4_FT_DIR             2
1470 #define EXT4_FT_CHRDEV          3
1471 #define EXT4_FT_BLKDEV          4
1472 #define EXT4_FT_FIFO            5
1473 #define EXT4_FT_SOCK            6
1474 #define EXT4_FT_SYMLINK         7
1475
1476 #define EXT4_FT_MAX             8
1477
1478 /*
1479  * EXT4_DIR_PAD defines the directory entries boundaries
1480  *
1481  * NOTE: It must be a multiple of 4
1482  */
1483 #define EXT4_DIR_PAD                    4
1484 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1485 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1486                                          ~EXT4_DIR_ROUND)
1487 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1488
1489 /*
1490  * If we ever get support for fs block sizes > page_size, we'll need
1491  * to remove the #if statements in the next two functions...
1492  */
1493 static inline unsigned int
1494 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1495 {
1496         unsigned len = le16_to_cpu(dlen);
1497
1498 #if (PAGE_CACHE_SIZE >= 65536)
1499         if (len == EXT4_MAX_REC_LEN || len == 0)
1500                 return blocksize;
1501         return (len & 65532) | ((len & 3) << 16);
1502 #else
1503         return len;
1504 #endif
1505 }
1506
1507 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1508 {
1509         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1510                 BUG();
1511 #if (PAGE_CACHE_SIZE >= 65536)
1512         if (len < 65536)
1513                 return cpu_to_le16(len);
1514         if (len == blocksize) {
1515                 if (blocksize == 65536)
1516                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1517                 else
1518                         return cpu_to_le16(0);
1519         }
1520         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1521 #else
1522         return cpu_to_le16(len);
1523 #endif
1524 }
1525
1526 /*
1527  * Hash Tree Directory indexing
1528  * (c) Daniel Phillips, 2001
1529  */
1530
1531 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1532                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1533                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1534 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1535 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1536
1537 /* Legal values for the dx_root hash_version field: */
1538
1539 #define DX_HASH_LEGACY          0
1540 #define DX_HASH_HALF_MD4        1
1541 #define DX_HASH_TEA             2
1542 #define DX_HASH_LEGACY_UNSIGNED 3
1543 #define DX_HASH_HALF_MD4_UNSIGNED       4
1544 #define DX_HASH_TEA_UNSIGNED            5
1545
1546 #ifdef __KERNEL__
1547
1548 /* hash info structure used by the directory hash */
1549 struct dx_hash_info
1550 {
1551         u32             hash;
1552         u32             minor_hash;
1553         int             hash_version;
1554         u32             *seed;
1555 };
1556
1557 #define EXT4_HTREE_EOF  0x7fffffff
1558
1559 /*
1560  * Control parameters used by ext4_htree_next_block
1561  */
1562 #define HASH_NB_ALWAYS          1
1563
1564
1565 /*
1566  * Describe an inode's exact location on disk and in memory
1567  */
1568 struct ext4_iloc
1569 {
1570         struct buffer_head *bh;
1571         unsigned long offset;
1572         ext4_group_t block_group;
1573 };
1574
1575 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1576 {
1577         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1578 }
1579
1580 /*
1581  * This structure is stuffed into the struct file's private_data field
1582  * for directories.  It is where we put information so that we can do
1583  * readdir operations in hash tree order.
1584  */
1585 struct dir_private_info {
1586         struct rb_root  root;
1587         struct rb_node  *curr_node;
1588         struct fname    *extra_fname;
1589         loff_t          last_pos;
1590         __u32           curr_hash;
1591         __u32           curr_minor_hash;
1592         __u32           next_hash;
1593 };
1594
1595 /* calculate the first block number of the group */
1596 static inline ext4_fsblk_t
1597 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1598 {
1599         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1600                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1601 }
1602
1603 /*
1604  * Special error return code only used by dx_probe() and its callers.
1605  */
1606 #define ERR_BAD_DX_DIR  -75000
1607
1608 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1609                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1610
1611 /*
1612  * Timeout and state flag for lazy initialization inode thread.
1613  */
1614 #define EXT4_DEF_LI_WAIT_MULT                   10
1615 #define EXT4_DEF_LI_MAX_START_DELAY             5
1616 #define EXT4_LAZYINIT_QUIT                      0x0001
1617 #define EXT4_LAZYINIT_RUNNING                   0x0002
1618
1619 /*
1620  * Lazy inode table initialization info
1621  */
1622 struct ext4_lazy_init {
1623         unsigned long           li_state;
1624         struct list_head        li_request_list;
1625         struct mutex            li_list_mtx;
1626 };
1627
1628 struct ext4_li_request {
1629         struct super_block      *lr_super;
1630         struct ext4_sb_info     *lr_sbi;
1631         ext4_group_t            lr_next_group;
1632         struct list_head        lr_request;
1633         unsigned long           lr_next_sched;
1634         unsigned long           lr_timeout;
1635 };
1636
1637 struct ext4_features {
1638         struct kobject f_kobj;
1639         struct completion f_kobj_unregister;
1640 };
1641
1642 /*
1643  * This structure will be used for multiple mount protection. It will be
1644  * written into the block number saved in the s_mmp_block field in the
1645  * superblock. Programs that check MMP should assume that if
1646  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1647  * to use the filesystem, regardless of how old the timestamp is.
1648  */
1649 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1650 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1651 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1652 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1653
1654 struct mmp_struct {
1655         __le32  mmp_magic;              /* Magic number for MMP */
1656         __le32  mmp_seq;                /* Sequence no. updated periodically */
1657
1658         /*
1659          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1660          * purposes and do not affect the correctness of the algorithm
1661          */
1662         __le64  mmp_time;               /* Time last updated */
1663         char    mmp_nodename[64];       /* Node which last updated MMP block */
1664         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1665
1666         /*
1667          * mmp_check_interval is used to verify if the MMP block has been
1668          * updated on the block device. The value is updated based on the
1669          * maximum time to write the MMP block during an update cycle.
1670          */
1671         __le16  mmp_check_interval;
1672
1673         __le16  mmp_pad1;
1674         __le32  mmp_pad2[227];
1675 };
1676
1677 /* arguments passed to the mmp thread */
1678 struct mmpd_data {
1679         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1680         struct super_block *sb;  /* super block of the fs */
1681 };
1682
1683 /*
1684  * Check interval multiplier
1685  * The MMP block is written every update interval and initially checked every
1686  * update interval x the multiplier (the value is then adapted based on the
1687  * write latency). The reason is that writes can be delayed under load and we
1688  * don't want readers to incorrectly assume that the filesystem is no longer
1689  * in use.
1690  */
1691 #define EXT4_MMP_CHECK_MULT             2UL
1692
1693 /*
1694  * Minimum interval for MMP checking in seconds.
1695  */
1696 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1697
1698 /*
1699  * Maximum interval for MMP checking in seconds.
1700  */
1701 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1702
1703 /*
1704  * Function prototypes
1705  */
1706
1707 /*
1708  * Ok, these declarations are also in <linux/kernel.h> but none of the
1709  * ext4 source programs needs to include it so they are duplicated here.
1710  */
1711 # define NORET_TYPE     /**/
1712 # define ATTRIB_NORET   __attribute__((noreturn))
1713 # define NORET_AND      noreturn,
1714
1715 /* bitmap.c */
1716 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1717
1718 /* balloc.c */
1719 extern unsigned int ext4_block_group(struct super_block *sb,
1720                         ext4_fsblk_t blocknr);
1721 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1722                         ext4_fsblk_t blocknr);
1723 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1724 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1725                         ext4_group_t group);
1726 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1727                                          ext4_fsblk_t goal,
1728                                          unsigned int flags,
1729                                          unsigned long *count,
1730                                          int *errp);
1731 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
1732                                   s64 nblocks, unsigned int flags);
1733 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1734 extern void ext4_check_blocks_bitmap(struct super_block *);
1735 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1736                                                     ext4_group_t block_group,
1737                                                     struct buffer_head ** bh);
1738 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1739 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1740                                       ext4_group_t block_group);
1741 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
1742                                        struct buffer_head *bh,
1743                                        ext4_group_t group,
1744                                        struct ext4_group_desc *desc);
1745 #define ext4_free_blocks_after_init(sb, group, desc)                    \
1746                 ext4_init_block_bitmap(sb, NULL, group, desc)
1747 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1748
1749 /* dir.c */
1750 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1751                                   struct file *,
1752                                   struct ext4_dir_entry_2 *,
1753                                   struct buffer_head *, unsigned int);
1754 #define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1755         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1756                                         (de), (bh), (offset)))
1757 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1758                                     __u32 minor_hash,
1759                                     struct ext4_dir_entry_2 *dirent);
1760 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1761
1762 /* fsync.c */
1763 extern int ext4_sync_file(struct file *, int);
1764 extern int ext4_flush_completed_IO(struct inode *);
1765
1766 /* hash.c */
1767 extern int ext4fs_dirhash(const char *name, int len, struct
1768                           dx_hash_info *hinfo);
1769
1770 /* ialloc.c */
1771 extern struct inode *ext4_new_inode(handle_t *, struct inode *, int,
1772                                     const struct qstr *qstr, __u32 goal);
1773 extern void ext4_free_inode(handle_t *, struct inode *);
1774 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1775 extern unsigned long ext4_count_free_inodes(struct super_block *);
1776 extern unsigned long ext4_count_dirs(struct super_block *);
1777 extern void ext4_check_inodes_bitmap(struct super_block *);
1778 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1779 extern int ext4_init_inode_table(struct super_block *sb,
1780                                  ext4_group_t group, int barrier);
1781
1782 /* mballoc.c */
1783 extern long ext4_mb_stats;
1784 extern long ext4_mb_max_to_scan;
1785 extern int ext4_mb_init(struct super_block *, int);
1786 extern int ext4_mb_release(struct super_block *);
1787 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1788                                 struct ext4_allocation_request *, int *);
1789 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1790 extern void ext4_discard_preallocations(struct inode *);
1791 extern int __init ext4_init_mballoc(void);
1792 extern void ext4_exit_mballoc(void);
1793 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1794                              struct buffer_head *bh, ext4_fsblk_t block,
1795                              unsigned long count, int flags);
1796 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1797                 ext4_group_t i, struct ext4_group_desc *desc);
1798 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1799                                 ext4_fsblk_t block, unsigned long count);
1800 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1801
1802 /* inode.c */
1803 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1804                                                 ext4_lblk_t, int, int *);
1805 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1806                                                 ext4_lblk_t, int, int *);
1807 int ext4_get_block(struct inode *inode, sector_t iblock,
1808                                 struct buffer_head *bh_result, int create);
1809
1810 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1811 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
1812 extern int  ext4_setattr(struct dentry *, struct iattr *);
1813 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1814                                 struct kstat *stat);
1815 extern void ext4_evict_inode(struct inode *);
1816 extern void ext4_clear_inode(struct inode *);
1817 extern int  ext4_sync_inode(handle_t *, struct inode *);
1818 extern void ext4_dirty_inode(struct inode *, int);
1819 extern int ext4_change_inode_journal_flag(struct inode *, int);
1820 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1821 extern int ext4_can_truncate(struct inode *inode);
1822 extern void ext4_truncate(struct inode *);
1823 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
1824 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1825 extern void ext4_set_inode_flags(struct inode *);
1826 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1827 extern int ext4_alloc_da_blocks(struct inode *inode);
1828 extern void ext4_set_aops(struct inode *inode);
1829 extern int ext4_writepage_trans_blocks(struct inode *);
1830 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1831 extern int ext4_block_truncate_page(handle_t *handle,
1832                 struct address_space *mapping, loff_t from);
1833 extern int ext4_block_zero_page_range(handle_t *handle,
1834                 struct address_space *mapping, loff_t from, loff_t length);
1835 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1836 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1837 extern void ext4_da_update_reserve_space(struct inode *inode,
1838                                         int used, int quota_claim);
1839
1840 /* indirect.c */
1841 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
1842                                 struct ext4_map_blocks *map, int flags);
1843 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
1844                                 const struct iovec *iov, loff_t offset,
1845                                 unsigned long nr_segs);
1846 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
1847 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
1848 extern void ext4_ind_truncate(struct inode *inode);
1849
1850 /* ioctl.c */
1851 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1852 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1853
1854 /* migrate.c */
1855 extern int ext4_ext_migrate(struct inode *);
1856
1857 /* namei.c */
1858 extern int ext4_orphan_add(handle_t *, struct inode *);
1859 extern int ext4_orphan_del(handle_t *, struct inode *);
1860 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1861                                 __u32 start_minor_hash, __u32 *next_hash);
1862
1863 /* resize.c */
1864 extern int ext4_group_add(struct super_block *sb,
1865                                 struct ext4_new_group_data *input);
1866 extern int ext4_group_extend(struct super_block *sb,
1867                                 struct ext4_super_block *es,
1868                                 ext4_fsblk_t n_blocks_count);
1869
1870 /* super.c */
1871 extern void __ext4_error(struct super_block *, const char *, unsigned int,
1872                          const char *, ...)
1873         __attribute__ ((format (printf, 4, 5)));
1874 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
1875                                                      __LINE__, ## message)
1876 extern void ext4_error_inode(struct inode *, const char *, unsigned int,
1877                              ext4_fsblk_t, const char *, ...)
1878         __attribute__ ((format (printf, 5, 6)));
1879 extern void ext4_error_file(struct file *, const char *, unsigned int,
1880                             ext4_fsblk_t, const char *, ...)
1881         __attribute__ ((format (printf, 5, 6)));
1882 extern void __ext4_std_error(struct super_block *, const char *,
1883                              unsigned int, int);
1884 extern void __ext4_abort(struct super_block *, const char *, unsigned int,
1885                        const char *, ...)
1886         __attribute__ ((format (printf, 4, 5)));
1887 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
1888                                                        __LINE__, ## message)
1889 extern void __ext4_warning(struct super_block *, const char *, unsigned int,
1890                           const char *, ...)
1891         __attribute__ ((format (printf, 4, 5)));
1892 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
1893                                                        __LINE__, ## message)
1894 extern void ext4_msg(struct super_block *, const char *, const char *, ...)
1895         __attribute__ ((format (printf, 3, 4)));
1896 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
1897                            const char *, unsigned int, const char *);
1898 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
1899                                                        __LINE__, msg)
1900 extern void __ext4_grp_locked_error(const char *, unsigned int, \
1901                                     struct super_block *, ext4_group_t, \
1902                                     unsigned long, ext4_fsblk_t, \
1903                                     const char *, ...)
1904         __attribute__ ((format (printf, 7, 8)));
1905 #define ext4_grp_locked_error(sb, grp, message...) \
1906         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
1907 extern void ext4_update_dynamic_rev(struct super_block *sb);
1908 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1909                                         __u32 compat);
1910 extern int ext4_update_rocompat_feature(handle_t *handle,
1911                                         struct super_block *sb, __u32 rocompat);
1912 extern int ext4_update_incompat_feature(handle_t *handle,
1913                                         struct super_block *sb, __u32 incompat);
1914 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1915                                       struct ext4_group_desc *bg);
1916 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1917                                       struct ext4_group_desc *bg);
1918 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1919                                      struct ext4_group_desc *bg);
1920 extern __u32 ext4_free_blks_count(struct super_block *sb,
1921                                 struct ext4_group_desc *bg);
1922 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1923                                  struct ext4_group_desc *bg);
1924 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1925                                 struct ext4_group_desc *bg);
1926 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1927                                    struct ext4_group_desc *bg);
1928 extern void ext4_block_bitmap_set(struct super_block *sb,
1929                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1930 extern void ext4_inode_bitmap_set(struct super_block *sb,
1931                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1932 extern void ext4_inode_table_set(struct super_block *sb,
1933                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1934 extern void ext4_free_blks_set(struct super_block *sb,
1935                                struct ext4_group_desc *bg, __u32 count);
1936 extern void ext4_free_inodes_set(struct super_block *sb,
1937                                 struct ext4_group_desc *bg, __u32 count);
1938 extern void ext4_used_dirs_set(struct super_block *sb,
1939                                 struct ext4_group_desc *bg, __u32 count);
1940 extern void ext4_itable_unused_set(struct super_block *sb,
1941                                    struct ext4_group_desc *bg, __u32 count);
1942 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
1943                                    struct ext4_group_desc *gdp);
1944 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
1945                                        struct ext4_group_desc *gdp);
1946
1947 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1948 {
1949         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1950                 le32_to_cpu(es->s_blocks_count_lo);
1951 }
1952
1953 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1954 {
1955         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1956                 le32_to_cpu(es->s_r_blocks_count_lo);
1957 }
1958
1959 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1960 {
1961         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1962                 le32_to_cpu(es->s_free_blocks_count_lo);
1963 }
1964
1965 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1966                                          ext4_fsblk_t blk)
1967 {
1968         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1969         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1970 }
1971
1972 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1973                                               ext4_fsblk_t blk)
1974 {
1975         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1976         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1977 }
1978
1979 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1980                                            ext4_fsblk_t blk)
1981 {
1982         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1983         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1984 }
1985
1986 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1987 {
1988         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1989                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1990                         le32_to_cpu(raw_inode->i_size_lo);
1991         else
1992                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1993 }
1994
1995 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1996 {
1997         raw_inode->i_size_lo = cpu_to_le32(i_size);
1998         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1999 }
2000
2001 static inline
2002 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2003                                             ext4_group_t group)
2004 {
2005          struct ext4_group_info ***grp_info;
2006          long indexv, indexh;
2007          grp_info = EXT4_SB(sb)->s_group_info;
2008          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2009          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2010          return grp_info[indexv][indexh];
2011 }
2012
2013 /*
2014  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2015  * the locking protocol documented in the comments of ext4_group_add()
2016  * in resize.c
2017  */
2018 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2019 {
2020         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2021
2022         smp_rmb();
2023         return ngroups;
2024 }
2025
2026 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2027                                              ext4_group_t block_group)
2028 {
2029         return block_group >> sbi->s_log_groups_per_flex;
2030 }
2031
2032 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2033 {
2034         return 1 << sbi->s_log_groups_per_flex;
2035 }
2036
2037 #define ext4_std_error(sb, errno)                               \
2038 do {                                                            \
2039         if ((errno))                                            \
2040                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2041 } while (0)
2042
2043 #ifdef CONFIG_SMP
2044 /* Each CPU can accumulate percpu_counter_batch blocks in their local
2045  * counters. So we need to make sure we have free blocks more
2046  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2047  */
2048 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2049 #else
2050 #define EXT4_FREEBLOCKS_WATERMARK 0
2051 #endif
2052
2053 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2054 {
2055         /*
2056          * XXX: replace with spinlock if seen contended -bzzz
2057          */
2058         down_write(&EXT4_I(inode)->i_data_sem);
2059         if (newsize > EXT4_I(inode)->i_disksize)
2060                 EXT4_I(inode)->i_disksize = newsize;
2061         up_write(&EXT4_I(inode)->i_data_sem);
2062         return ;
2063 }
2064
2065 struct ext4_group_info {
2066         unsigned long   bb_state;
2067         struct rb_root  bb_free_root;
2068         ext4_grpblk_t   bb_first_free;  /* first free block */
2069         ext4_grpblk_t   bb_free;        /* total free blocks */
2070         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2071         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2072         struct          list_head bb_prealloc_list;
2073 #ifdef DOUBLE_CHECK
2074         void            *bb_bitmap;
2075 #endif
2076         struct rw_semaphore alloc_sem;
2077         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2078                                          * regions, index is order.
2079                                          * bb_counters[3] = 5 means
2080                                          * 5 free 8-block regions. */
2081 };
2082
2083 #define EXT4_GROUP_INFO_NEED_INIT_BIT   0
2084
2085 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2086         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2087
2088 #define EXT4_MAX_CONTENTION             8
2089 #define EXT4_CONTENTION_THRESHOLD       2
2090
2091 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2092                                               ext4_group_t group)
2093 {
2094         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2095 }
2096
2097 /*
2098  * Returns true if the filesystem is busy enough that attempts to
2099  * access the block group locks has run into contention.
2100  */
2101 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2102 {
2103         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2104 }
2105
2106 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2107 {
2108         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2109         if (spin_trylock(lock))
2110                 /*
2111                  * We're able to grab the lock right away, so drop the
2112                  * lock contention counter.
2113                  */
2114                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2115         else {
2116                 /*
2117                  * The lock is busy, so bump the contention counter,
2118                  * and then wait on the spin lock.
2119                  */
2120                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2121                                   EXT4_MAX_CONTENTION);
2122                 spin_lock(lock);
2123         }
2124 }
2125
2126 static inline void ext4_unlock_group(struct super_block *sb,
2127                                         ext4_group_t group)
2128 {
2129         spin_unlock(ext4_group_lock_ptr(sb, group));
2130 }
2131
2132 static inline void ext4_mark_super_dirty(struct super_block *sb)
2133 {
2134         if (EXT4_SB(sb)->s_journal == NULL)
2135                 sb->s_dirt =1;
2136 }
2137
2138 /*
2139  * Block validity checking
2140  */
2141 #define ext4_check_indirect_blockref(inode, bh)                         \
2142         ext4_check_blockref(__func__, __LINE__, inode,                  \
2143                             (__le32 *)(bh)->b_data,                     \
2144                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2145
2146 #define ext4_ind_check_inode(inode)                                     \
2147         ext4_check_blockref(__func__, __LINE__, inode,                  \
2148                             EXT4_I(inode)->i_data,                      \
2149                             EXT4_NDIR_BLOCKS)
2150
2151 /*
2152  * Inodes and files operations
2153  */
2154
2155 /* dir.c */
2156 extern const struct file_operations ext4_dir_operations;
2157
2158 /* file.c */
2159 extern const struct inode_operations ext4_file_inode_operations;
2160 extern const struct file_operations ext4_file_operations;
2161 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2162
2163 /* namei.c */
2164 extern const struct inode_operations ext4_dir_inode_operations;
2165 extern const struct inode_operations ext4_special_inode_operations;
2166 extern struct dentry *ext4_get_parent(struct dentry *child);
2167
2168 /* symlink.c */
2169 extern const struct inode_operations ext4_symlink_inode_operations;
2170 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2171
2172 /* block_validity */
2173 extern void ext4_release_system_zone(struct super_block *sb);
2174 extern int ext4_setup_system_zone(struct super_block *sb);
2175 extern int __init ext4_init_system_zone(void);
2176 extern void ext4_exit_system_zone(void);
2177 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2178                                  ext4_fsblk_t start_blk,
2179                                  unsigned int count);
2180 extern int ext4_check_blockref(const char *, unsigned int,
2181                                struct inode *, __le32 *, unsigned int);
2182
2183 /* extents.c */
2184 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2185 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2186 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2187                                        int chunk);
2188 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2189                                struct ext4_map_blocks *map, int flags);
2190 extern void ext4_ext_truncate(struct inode *);
2191 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2192                                 loff_t length);
2193 extern void ext4_ext_init(struct super_block *);
2194 extern void ext4_ext_release(struct super_block *);
2195 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2196                           loff_t len);
2197 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2198                           ssize_t len);
2199 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2200                            struct ext4_map_blocks *map, int flags);
2201 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2202                         __u64 start, __u64 len);
2203 /* move_extent.c */
2204 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2205                              __u64 start_orig, __u64 start_donor,
2206                              __u64 len, __u64 *moved_len);
2207
2208 /* page-io.c */
2209 extern int __init ext4_init_pageio(void);
2210 extern void ext4_exit_pageio(void);
2211 extern void ext4_ioend_wait(struct inode *);
2212 extern void ext4_free_io_end(ext4_io_end_t *io);
2213 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2214 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2215 extern void ext4_io_submit(struct ext4_io_submit *io);
2216 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2217                                struct page *page,
2218                                int len,
2219                                struct writeback_control *wbc);
2220
2221 /* mmp.c */
2222 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2223
2224 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2225 enum ext4_state_bits {
2226         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2227           = BH_JBDPrivateStart,
2228 };
2229
2230 BUFFER_FNS(Uninit, uninit)
2231 TAS_BUFFER_FNS(Uninit, uninit)
2232
2233 /*
2234  * Add new method to test wether block and inode bitmaps are properly
2235  * initialized. With uninit_bg reading the block from disk is not enough
2236  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2237  */
2238 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2239
2240 static inline int bitmap_uptodate(struct buffer_head *bh)
2241 {
2242         return (buffer_uptodate(bh) &&
2243                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2244 }
2245 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2246 {
2247         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2248 }
2249
2250 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2251
2252 /* For ioend & aio unwritten conversion wait queues */
2253 #define EXT4_WQ_HASH_SZ         37
2254 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2255                                             EXT4_WQ_HASH_SZ])
2256 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2257                                              EXT4_WQ_HASH_SZ])
2258 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2259 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2260
2261 #endif  /* __KERNEL__ */
2262
2263 #endif  /* _EXT4_H */